Overview

The advantages of acid etching come from one fact: metal is removed by a controlled chemical reaction instead of force or heat, so parts leave the line flat, burr-free and stress-free. First, there are no mechanical burrs or roll-over, so secondary deburring disappears. Second, because no hard die is needed, a new part number is only a new phototool, which keeps prototypes and low volumes economical. Third, features down to about 0.05 mm hold at production thickness without the distortion a punch or a laser heat-affected zone would introduce.

Further advantages of acid etching are repeatability and material freedom: the same film reproduces identical apertures from the first article to high volume, and stainless steel, copper, brass, nickel and Kovar all run on one line with passivation or plating matched to the end environment. There is no tool wear to drift dimensions, no residual stress to warp thin foils, and design revisions cost days rather than weeks. For precision electronics, medical, automotive and filtration assemblies, these advantages of acid etching add up to tighter fit, less rework and a shorter path from prototype to production.

Parameter Window

• Available Materials: stainless steel 304/316L, copper, brass, nickel, Kovar, titanium
• Material Thickness Range: 0.02–2.0 mm
• Tolerance: ±0.02 mm on critical profiles (down to ±0.01 mm on thin stock)
• Minimum Feature: 0.05 mm line width, 0.08 mm hole diameter at 0.1 mm stock
• Surface Options: passivation, electropolish, Ni/Au plating, black oxide, adhesive backing
• Compliance: ISO 9001 process control, RoHS/REACH material traceability

Manufacturing Process / Workflow (8 Steps)

1. Artwork & DFM Review — Convert the drawing into vector artwork and check hole diameters, web widths and bend relief against 0.02–2.0 mm stock before tooling.
2. Material Selection — Choose stainless steel, copper and nickel alloys in the right temper and confirm flatness before lamination.
3. Cleaning & Lamination — Degrease the sheet and laminate dry-film photoresist on both faces under controlled heat and pressure.
4. UV Exposure — Expose the pattern through high-resolution film registered to the sheet datum for panel-level accuracy.
5. Development — Wash out unexposed resist to open the apertures, then inspect the finest features for residue.
6. Controlled Etching — Spray or immerse in chemistry matched to the alloy, holding ±0.02 mm through time, temperature and conveyor speed.
7. Stripping & Finishing — Remove resist, neutralize, then apply passivation or plating and optional anneal for flatness.
8. Inspection & Packaging — Verify aperture size, profile and flatness against the approved first article, then pack in trays or on liner.

Core Advantages

1. Burr-free edges: Chemical removal leaves no roll-over or heat tint, so parts seat flush without secondary deburring.
2. No hard tooling: A new part number is a new film, keeping low-volume programs economical.
3. Fine feature capability: Features down to 0.05 mm hold at production thickness without distortion.
4. Tight, repeatable tolerance: ±0.02 mm is held across the whole sheet, so assemblies fit without selective rework.
5. Stress-free flat parts: No mechanical force means thin parts stay flat and dimensionally stable after etching.
6. Material and finish flexibility: Stainless, copper and nickel alloys run on one line with matched plating or passivation.

Typical Applications

• Lead frames: Etched IC and semiconductor lead frames with fine, burr-free fingers.
• Encoder discs: High-resolution optical encoder discs with dense slot patterns.
• Shims and spacers: Precision thickness shims for instrument gap control.
• Filter meshes: Micro-perforated screens for filtration and metering.
• EMI shielding: Thin shielding cans and meshes for RF-sensitive modules.
• Aperture plates: Optical apertures and masks for imaging and sensing.

Design Notes & Process Considerations

1. Feature versus thickness: Keep the minimum web at or above 1.2 × material thickness so narrow ribs do not lift during etching.
2. Tolerance callout: State ±0.02 mm on critical profiles and separate half-etched depth from through-cut dimensions.
3. Hole geometry: Specify diameter, pitch and open area; round entries reduce stress concentration.
4. Flatness and burr: Call out flatness per 100 mm and require burr-free edges where parts mate to a housing.
5. Surface and plating: Name the finish and thickness, since plating adds to the final thickness stack.
6. Panelization: Group parts with shared registration marks to cut handling cost on repeat volumes.